Good morning.
What’s the best method of insulating the firebox on a Lune Valley boiler?
At present mine has only the sides fitted.
TIA
Ian
Lune Valley Boiler - firebox insulation ?
-
- Full Steam Ahead
- Posts: 154
- Joined: Wed Jan 11, 2017 12:30 pm
- Boat Name: Isambard
- Location: Calstock, Cornwall, UK
- barts
- Full Steam Ahead
- Posts: 1069
- Joined: Wed Nov 18, 2009 6:08 am
- Boat Name: Otter, Rainbow
- Location: Lopez Island, WA and sometimes Menlo Park, CA
- Contact:
Re: Lune Valley Boiler - firebox insulation ?
If the flame never contacts the walls, a thin high temp. stainless (US alloy designation 310) sheet backed w/ Fiberfrax or similar insulation works well. If the burner washes the walls with flame, you'll want a castable refractory, I think, in order to last.
- Bart
- Bart
-------
Bart Smaalders http://smaalders.net/barts Lopez Island, WA
Bart Smaalders http://smaalders.net/barts Lopez Island, WA
-
- Full Steam Ahead
- Posts: 179
- Joined: Sun Jun 05, 2011 7:08 am
- Boat Name: Blue Buccaneer
- Location: Wallasey
Re: Lune Valley Boiler - firebox insulation ?
Hi Ian, on my lune valley boiler (solid fuel) I made the casing out of 25mm square tubing. I could then use a ceramic fibre insulation about the same thick ness . I clad the out side in stainless steel about 1mm thick, on the inside of the fibre insulation I used a stainless steel mesh to hold the fibre in place.
I had a old kilm and used the soild bricks out of that around the grate so the 'coals' do not touch the ceramic fibre. I also used these alongside the bottom drum . High for the solid bricks is just over want I thought the fire might be and are about 4- 5 inches high. On the back wall I used taller slabs of these fire bricks about 8 inchs high . I also stuffed ceramic fibre around the outside of the two drums . It has done a seasons firing as is all OK.
The out side temperature of the boiler varies , just warm to the touch on the 2 drum side to just a bit to hot to hold your hand agaist it on the other but still no where hot engouh to burn.
Mike
I had a old kilm and used the soild bricks out of that around the grate so the 'coals' do not touch the ceramic fibre. I also used these alongside the bottom drum . High for the solid bricks is just over want I thought the fire might be and are about 4- 5 inches high. On the back wall I used taller slabs of these fire bricks about 8 inchs high . I also stuffed ceramic fibre around the outside of the two drums . It has done a seasons firing as is all OK.
The out side temperature of the boiler varies , just warm to the touch on the 2 drum side to just a bit to hot to hold your hand agaist it on the other but still no where hot engouh to burn.
Mike
Mike Cole
-
- Full Steam Ahead
- Posts: 154
- Joined: Wed Jan 11, 2017 12:30 pm
- Boat Name: Isambard
- Location: Calstock, Cornwall, UK
Re: Lune Valley Boiler - firebox insulation ?
Brilliant, just what I needed to know.Mike Cole wrote:Hi Ian, on my lune valley boiler (solid fuel) I made the casing out of 25mm square tubing. I could then use a ceramic fibre insulation about the same thick ness . I clad the out side in stainless steel about 1mm thick, on the inside of the fibre insulation I used a stainless steel mesh to hold the fibre in place.
I had a old kilm and used the soild bricks out of that around the grate so the 'coals' do not touch the ceramic fibre. I also used these alongside the bottom drum . High for the solid bricks is just over want I thought the fire might be and are about 4- 5 inches high. On the back wall I used taller slabs of these fire bricks about 8 inchs high . I also stuffed ceramic fibre around the outside of the two drums . It has done a seasons firing as is all OK.
The out side temperature of the boiler varies , just warm to the touch on the 2 drum side to just a bit to hot to hold your hand agaist it on the other but still no where hot engouh to burn.
Mike
Thanks
Ian
-
- Full Steam Ahead
- Posts: 154
- Joined: Wed Jan 11, 2017 12:30 pm
- Boat Name: Isambard
- Location: Calstock, Cornwall, UK
Re: Lune Valley Boiler - firebox insulation ?
What’s the reason for stuffing the ceramic fibre around the outside of the two drums?Mike Cole wrote:Hi Ian, on my lune valley boiler (solid fuel) I made the casing out of 25mm square tubing. I could then use a ceramic fibre insulation about the same thick ness . I clad the out side in stainless steel about 1mm thick, on the inside of the fibre insulation I used a stainless steel mesh to hold the fibre in place.
I had a old kilm and used the soild bricks out of that around the grate so the 'coals' do not touch the ceramic fibre. I also used these alongside the bottom drum . High for the solid bricks is just over want I thought the fire might be and are about 4- 5 inches high. On the back wall I used taller slabs of these fire bricks about 8 inchs high . I also stuffed ceramic fibre around the outside of the two drums . It has done a seasons firing as is all OK.
The out side temperature of the boiler varies , just warm to the touch on the 2 drum side to just a bit to hot to hold your hand agaist it on the other but still no where hot engouh to burn.
Mike
Thanks
Ian
- barts
- Full Steam Ahead
- Posts: 1069
- Joined: Wed Nov 18, 2009 6:08 am
- Boat Name: Otter, Rainbow
- Location: Lopez Island, WA and sometimes Menlo Park, CA
- Contact:
Re: Lune Valley Boiler - firebox insulation ?
Ceramic fiber insulation works very well, but cannot handle either direct oil flame impingement or regular casual contact with solid fuels such as coal or wood. Thus, the firebox itself needs an inner liner that can both deal with the temperatures and the contact. This liner material can be a relatively poor insulator; it's principle job is to protect the ceramic fiber. I've used insulating firebrick, stainless steel and castable refractory for this task in an oil fired boiler; the relatively weak firebrick could not handle the shock loads from getting trailered several thousand miles, and the stainless steel lasted 15 years but should have been replaced earlier. The castable refractory has proven quite sturdy and shock resistant although somewhat heavy.
Such construction is common in home built oil fired foundry furnaces.
- Bart
Such construction is common in home built oil fired foundry furnaces.
- Bart
-------
Bart Smaalders http://smaalders.net/barts Lopez Island, WA
Bart Smaalders http://smaalders.net/barts Lopez Island, WA
-
- Full Steam Ahead
- Posts: 179
- Joined: Sun Jun 05, 2011 7:08 am
- Boat Name: Blue Buccaneer
- Location: Wallasey
Re: Lune Valley Boiler - firebox insulation ?
only on the outside side of the drum not the fire sideianrichards wrote:What’s the reason for stuffing the ceramic fibre around the outside of the two drums?Mike Cole wrote:Mike
Thanks
Ian
mike
Mike Cole